In the existing display device, the liquid crystal display (LCD) has the advantages of lower power consumption, high display quality, free of electromagnetic radiation and wide range of applications, and is a relatively important display device at present.
The liquid crystal display generally comprises a liquid crystal display panel and a backlight module for providing light sources for the liquid crystal display panel; wherein the liquid crystal display panel comprises a lower polarizer, an array substrate, a liquid crystal layer, a counter substrate and an upper polarizer from bottom to top successively; the light emitted from the backlight module is emitted to the array substrate in the liquid crystal display panel through the lower polarizer.
In the existing liquid crystal display, thin film transistors (TFT) and pixel electrodes are generally arranged at a side of the array substrate facing the liquid crystal layer, the light emitted from the backlight module will irradiate the TFT on the array substrate through the lower polarizer, the TFT on the array substrate will generate leakage current after being irradiated by the backlight. Take the bottom gate type TFT as an example for illustration, the gate electrode in the bottom gate type TFT is located below the active layer; theoretically, the gate electrode can shield the TFT channels from being irradiated by the backlight; however, it is difficult for the actual manufacturing process to ensure that all the TFT channels can be shielded by the gate electrode completely; moreover, the conditions of the TFT channels at different positions on the array substrate being irradiated by the backlight are different; therefore, the leakage currents generated by the TFTs at different positions on the array substrate will be different, thereby causing the voltages of the pixel electrodes at different positions on the array substrate to be different, generating defects such as flicker and crosstalk in the liquid crystal display, which may influence display quality of the liquid crystal display.